Tillandsia

((till and’ see uh))

Tillandsia, named for the Swedish physician Elias Tillands, is the largest genus in the subfamily Tillandsioidae. There are over 500 known species of Tillandsia, and more are being discovered every year. Somewhere I heard that when all is said and done, almost one half of all bromeliads will belong to this genus. This might be an exaggeration, but than again it might not be too far from the truth.

There are two major types of Tillandsias, those with hard leaves, and those with soft leaves. Since the culture differs for the two types, I will only discuss those with hard leaves in this article. The culture of Tillandsias with soft leaves (those whose are leaves similar to those of a Vriesea or a Guzmania ) will be discussed in a future article.

Tillandsias are the most widely dispersed of all the Bromeliads. They range from Virginia in the southern United States, through Central America and the West Indies, and as far south as southern Argentina. They can be found growing near sea level or as high as 3000 meters. Species of this genus can thrive in almost any exposure; from deep shade to full sunlight, some Tillandsia will be happy. They grow in rain forests, on beaches, even in deserts. They grow on tree trunks, branches, shrubs, cacti, rocks, cliff faces, and even sometimes in soil. Most members of this genus are epiphytes; however some are saxicolous, and a few are terrestrial. Almost all have small root systems functioning more to hold the plant stable than to absorb nutrients. Their sizes vary almost as much as their range. Some forms of ionantha are about 1 inch tall, while a large fasciculata can be over 40 inches tall. Three species (baileyi, recurvata, and usneoides) are native to Texas.

Flowers tend to be tubular and grow on one or more spikes. The bracts can range from almost colorless gray to flaming red, and the flowers themselves can be violet, blue, white, pink, or yellow. While most do not have a scent, some like crocata (cinnamon) and duratii (grape) have a strong odor that will perfume a large area.

Light:

They like bright light. In fact, some can take almost full sun in the Houston area. Most grow well in 30% to 70% shade which is about 3000 to 7000 foot candles. Plants with hard, thick, gray leaves with lots of scales tolerate the most light.

Green and gray-green thinner leaves need less light. If growing under artificial
lights, the day length should be between 10 and 16 hours. Longer or shorter
days can cause the plants to take on an abnormal appearance.

Temperature:

Tillandsias prefer temperatures in the range of 50-60 degrees Fahrenheit at night rising to 80-90 degrees in the daytime. They can tolerate temperatures in the low 20s for brief periods of time if given some protection(covered) or put on the south side. On the other hand, they do not appear to mind Houston’s hot, sunny summers, when the temperature climbs over 100 degrees.

Humidity:

A range of 50% to 70% is ideal. Mounted plants need higher humidity than potted plants. When the humidity falls below 50%, plants will need to be watered more heavily. Good air circulation is essential for good disease free growth. As the humidity and temperature increase so should the air circulation.

Fertilizer:

Try to avoid fertilizers that contain boron, copper or zinc; these elements are deadly to most Tillandsias. Most plants will survive fine with little or no fertilizer, but if you want to see them grow and bloom, they need food on a regular basis.

Almost any good water soluble acidic fertilizer will work. Dilute the fertilizer to
1/4th or even 1/8th strength and spray it onto the leaves every two weeks while
the plants are actively growing. It is best to avoid fertilizers that contain urea or
fish emulsion as these compounds need bacteria in the soil to break them down into a form of nitrogen that the plants can utilize.

Water:

Mounted plants tend to dry out quicker than potted plants. A little misting is usually not enough, drench the plants to the point of runoff whenever they are dry. Extremely dehydrated plants need to be soaked for an hour or two in a tub of water. The water should be slightly acidic, a pH of 6.5 is ideal, but they will tolerate a pH range from 4 to 8. The water should be low in calcium and magnesium salts, but if you use distilled water, add a little fertilizer so that it does not leach the nutrients out of the plants.

Medium:

Many plants will grow mounted on cork or wood. Those that are potted like a well drained medium such as a mixture of ½ small bark chips and ½ peat based soil less mix.

Containers:

Plants can be mounted on wood or any nontoxic substance. They will grow on almost anything: branches, cypress knees, roots, seashells, grapevine wreaths, rocks, and even a piece of monofilament fishing line. The main requirements are that the material does not rot quickly, and it is substantial enough for the plant to be firmly attached to it. Plants that wiggle will not send out roots and attach themselves to the mounting. Monofilament fishing line, strips of nylon stocking, water proof glue, nails, or staples can be used to attach plants to the mount. As mentioned earlier, they must be tied, glued, or nailed so that they do not move.

Most Tillandsias are grown mounted; if you want to try growing a few in pots, choose plants that have symmetrical rosettes of leaves, and use a small pot with a well drained mix. One warning, if the plant comes from a desert habitat, never pot it.

Propagation:

As with most Bromeliads, you can grow them from seed if your have the time and patience, however most people start with pups. The plants usually produce pups at their base after flowering, however some plants have pups on the inflorescence, and a few have pups and form a nice clump before they flower. Most growers don’t divide their plants on a regular basis; they let them multiply undisturbed for years. One little Tillandsia doesn’t make much of an impact, but a large well grown clump is truly a sight to behold.

Problems:

Plants with good growing conditions seldom are bothered by insects or fungus. The major insect problem is the larva of a small moth that feeds on the roots of Tillandsia clumps. Examine your plants on a monthly basis and if you see any damage, and especially if you see moths flying around your plants, treat with an Insecticide.

Although not a disease, pressure treated wood is deadly to Tillandsias. Since they absorb almost all of their nutrients through their leaves, they are very sensitive to the copper and other metals that leach out of treated lumber. It is best to avoid having any treated lumber near your Tillandsias.

Most hard leafed Tillandsia species and hybrids grow well in the Houston area, although we do have trouble with some of the ones that are native to the higher elevations. Some of the more popular species are:

argentea

baileyi

bulbosa

capitata

caput-medusae

concolor*

crocata*

duratii

fasciculata

hammeri

ionantha*

ixioides

juncea

recurvata

stricta

tricolor

tectorum*

usneoides

* indicates plants that will grow well in full sun in the Houston area.